The shift from spinning-disk storage or hard-disk drives to flash storage or solid-state drives has been a bit of a quiet revolution. Unless they’re tinkering with the insides of their computing devices, average consumers don’t notice what kind of storage their devices are running.

But IT workers do and the march of progress toward a flash-first future has been charging full steam ahead for the last 10 years.

When flash storage first made its debut on the computing scene in the late ’90s, it was too expensive to roll out at the level of HDDs. The small, low-capacity USB flash storage devices, however, quickly proved popular. Over time, the price of flash has dropped, and some analysts expect 2013 to be the year when flash storage gains equal footing on price with HDDs.

In a post on the Hitachi blog, Hu Yoshida, Hitachi vice president and chief technology officer, pinpoints Apple’s shift from HDD to flash storage for its iPod devices in 2007 as a watershed moment for the storage technology.

With flash storage’s ability to boost performance and process more data quickly, it’s easy to assume that flash will soon trump spinning disks completely. But Yoshida thinks we’re still a ways from that reality.

HDDs will still be able to provide larger capacities at lower cost. If it is used with flash in a dynamic tier of pooled resources, HDDs will be able to concentrate on increasing capacity without having to be so concerned about performance. While the technologies for increasing bit densities have slowed down, there are other ways to increase capacity such as through packaging as it was done with near line SAS. However, the future for high performance 15K RPM HDDs is not bright.

HDDs have another characteristic, which will ensure their continued use: durability. HDDs are approximately 1015 to 1016 while MLC flash is 103 to 104, in terms of re-writability.

Yoshida’s defense of HDD technology is precisely why many IT experts and companies are turning to hybrid storage solutions that combine the benefits of both SSD and HDD technology.

However, other IT experts, like Enterprise Strategy Group’s Steve Duplessie, are fast-forwarding to an all-flash future.

“Flash is going everywhere, so adopt, accept and move on. Wherever you can put it, put it,” Duplessie said at EMC World last year.

There isn’t really one answer for the HDD vs. SSD question. While advocates on both sides will root for their favorite team, we’ll probably live with both for another 10 years.

After all, tape storage was supposed to be extinct and replaced by disk-based storage by now, but one British university has just turned to tape as its backup solution. So don’t count HDDs out just yet.